29.4. Configure Multiple Site Masters

Procedure 29.4. Set Multiple Site Masters in Remote Client-Server Mode

1. Locate the Target Configuration

   Locate the target site's configuration in the clustered-xsite.xml example configuration file. The sample configuration looks like the following example:

   <relay site="LON">
   	<remote-site name="NYC" stack="tcp" cluster="global"/>
   	<remote-site name="SFO" stack="tcp" cluster="global"/>
   	<property name="relay_multicasts">false</property>
   </relay>

2. Configure Maximum Sites

   Use the max_site_masters property to determine the maximum number of master nodes within the site. Set this value to the number of nodes in the site to make every node a master.

   <relay site="LON">
   	<remote-site name="NYC" stack="tcp" cluster="global"/>
   	<remote-site name="SFO" stack="tcp" cluster="global"/>
   	<property name="relay_multicasts">false</property>
   	<property name="max_site_masters">16</property>
   </relay>

3. Configure Site Master

   Use the can_become_site_master property to allow the node to become the site master. This flag is set to true as a default. Setting this flag to false prevents the node from becoming a site master. This is required in situations where the node does not have a network interface connected to the external network.

   <relay site="LON">
   	<remote-site name="NYC" stack="tcp" cluster="global"/>
   	<remote-site name="SFO" stack="tcp" cluster="global"/>
   	<property name="relay_multicasts">false</property>
   	<property name="max_site_masters">16</property>
   	<property name="can_become_site_master">true</property>
   </relay>

Procedure 29.5. Configure Multiple Site Masters (Library Mode)

1. Configure Cross-Datacenter Replication

   Configure Cross-Datacenter Replication in JBoss Data Grid. Use the instructions in Section 29.2.2.1, “Configure Cross-Datacenter Replication Declaratively” for an XML configuration or the instructions in Section 29.2.2.2, “Configure Cross-Datacenter Replication Programmatically” for a programmatic configuration.

2. Add the Contents of the Configuration File

   Add the can_become_site_master and max_site_masters parameters to the configuration as follows:

   <config> 
       ... 
       <relay.RELAY2 site="LON" 
                 config="relay.xml" 
                 relay_multicasts="false"
                 can_become_site_master="true" 
                 max_site_masters="16"/>
   </config>

   Set the max_site_masters value to the number of nodes in the cluster to make all nodes masters.